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11/18/2019 – Ephemeris – More about the Leonid meteor shower that just reached peak this morning
Ephemeris for Monday, November 18th. Today the Sun will be up for 9 hours and 28 minutes, setting at 5:12, and it will rise tomorrow at 7:44. The Moon, 1 day before last quarter, will rise at 10:56 this evening.
The Leonid meteor shower should have reached its peak early this morning hindered by a bright waning gibbous Moon. In past years, usually every 33 years the Leonid meteors have a super peak, called a meteor storm, where thousands of meteors streak through the skies. These appear for a brief period over a rather small geographic area. In 1966 it occurred principally over the Rocky Mountains. The comet responsible is 55P/Comet Tempel-Tuttle, independently discovered by two astronomers Tempel and Tuttle in 1865 & 1866. The comet has a 33 year orbit of the Sun, and its orbit crosses very close to the Earth’s orbit. Comets are notorious litter bugs, shedding gas, dust and pebble sized debris as they come close to the warming rays of the Sun.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Leonid meteor shower as seen from space. The time is set for today so the Earth’s blue dot is lost in the stream of meteors crossing the Earth’s orbit (3rd one out from the Sun) just above the 9 o’clock position. The long ellipse is the orbit of Comet Tempel-Tuttle and the purple dot near the aphelion near Uranus’ orbit is the calculated current position of the comet. The flurry of dots are the calculated positions of meteors that whose orbits have been calculated. Click on the image to enlarge. Credit: NASA’s CAMS video camera surveillance network, and were calculated by meteor astronomer Peter Jenniskens of the SETI Institute and NASA Ames Research Center. This visualization is developed and hosted by Ian Webster.
These interactive animations can be found on the International Meteor Organization website: https://www.imo.net. under Resources and Meteor Shower Calendar.
11/17/2015 – Ephemeris – The Leonid peak is expected to be today and tonight
Ephemeris for Tuesday, November 17th. The Sun will rise at 7:42. It’ll be up for 9 hours and 30 minutes, setting at 5:12. The Moon, 2 days before first quarter, will set at 10:49 this evening.
The Leonid meteor shower is predicted to reach its peak or rather peaks today. One this afternoon is a newly computed peak, which we obviously cannot see, and another around 11 p.m. which occurs just before the radiant rises. The radiant is the point in the sky from which the meteors seem to come from, so to see any meteors that source point must be above the horizon. The Leonid meteors are the debris of Comet 55P/Tempel-Tuttle, which was discovered independently by Ernst Tempel in 1865 and Horace Tuttle 18 days later. The 55P in the name means that it was the 55th recognized periodic comet. It has a period of 33.24 years giving rise to meteor storms every 33 years or so. This isn’t one of those years.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
An all sky chart for 5 a.m for the Leonid meteor shower for 2015. Created by my LookingUp program. The yellow pattern marked LeoR is the Leonid radiant.
The orbit of 55P/Tempel-Tuttle near the Earth. The color or the orbit is lighter north of the Earth’s orbital plane. Note that the orbit of the comet crosses the Earth’s orbital plane as it passes just inside the Earth’s orbit. Created with JPL Small-Body Database Browser.
The entire orbit of 55P/Tempel-Tuttle. The color or the orbit is lighter north of the Earth’s orbital plane. Created with JPL Small-Body Database Browser.
Bob Moler's Ephemeris Blog 